RNA processing is a crucial step in gene expression that involves the modification of primary transcripts produced by RNA polymerase. This process includes various post-transcriptional modifications such as capping, splicing, polyadenylation, and editing, which are necessary to produce functional mRNA molecules that can be translated into proteins. RNA processing plays a significant role in regulating gene expression and can have profound effects on cellular function and development. Research in this area aims to understand the mechanisms and regulation of RNA processing, as well as its impact on gene expression, cellular function, and diseases.